The invention relates to a system for protecting persons who are engaged in underground operations from dangerous areas.
An important problem of underground operations is the automatic protection of persons engaged in certain kinds of work against any dangers that might occur, or the automatic counting of persons, or the automatic location of persons in spite of poor visibility, as caused, for example, by fire or an explosion, or the automatic location of persons buried by a collapsing support or section.
For the location of persons buried alive in mine disasters, the German Petty Pat. No. 6,805,398 suggests that the headlamp of each miner should be equipped with a transmitter, the signal of which can be detected. This arrangement, however, leaves unsolved other equally important aspects of the problem of mine safety, such as the protection of persons in dangerous areas or the counting of persons to ensure that an unsafe number of persons do not ride in the cage.